1. An area of land that has not been officially mapped, measured, or examined in detail by surveyors or cartographers
The explorers ventured into an unsurveyed region of the Amazon rainforest.
Os exploradores se aventuraram em uma região não mapeada da floresta amazônica.
2. Territory that lacks detailed geographical, topographical, or official documentation
Many unsurveyed regions remain in remote parts of Central Asia.
Muitas regiões não mapeadas permanecem em partes remotas da Ásia Central.